Ph / oxidation-reduction potential adjusted water manufacturing device, ph / oxidation-reduction potential adjusted water manufacturing method, and semiconductor device manufacturing method

Abstract

To provide a pH / oxidation-reduction potential adjusted water manufacturing device capable of dissolving a predetermined amount of wiring metal.SOLUTION: There is provided a pH / oxidation-reduction potential adjusted water manufacturing device 1 including: a hydrogen peroxide removing mechanism 3 for removing hydrogen peroxide dissolved in pure water W from the pure water, a first branch line 4, a second branch line 5, and a merging line 6, in which the first branch line 4 includes a first pH adjusting device 41A, an oxidation-reduction potential adjusting device 42A, and a first storage tank 43, which are arranged in this order, and the second branch line 5 includes a second pH adjusting device 51A and a second storage tank 53 arranged in this order, and the merging line 6 is configured to alternately circulate first adjusted water W1, pH of which has been adjusted to be within a range of 9 to 14 and an oxidation-reduction potential of which has been adjusted to be within a range of 0.1 to 1.0 V (vs Ag / AgCl) by the first branch line 4, and second adjusted water W2, pH of which has been adjusted to be within a range of 0 to 5 by the second branch line 5.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an apparatus for producing pH·redox potential adjusted water, a method for producing pH·redox potential adjusted water, and a method for manufacturing a semiconductor device.

Background Art

[0002] In recent years, although the miniaturization of semiconductors is approaching its limit, the need for higher functionality of semiconductors is increasing even more. Therefore, as a technology for high integration of semiconductors to replace the conventional miniaturization, a three-dimensional integration technology that improves the integration density per unit area by stacking semiconductors in the vertical direction has become an essential technology for next-generation semiconductor manufacturing.

[0003] Generally, the Wafer-to-Wafer (W2W) process is carried out through a process of wafer surface planarization, activation of the wafer surface by plasma, cleaning and hydrophilic treatment of the wafer surface by wafer cleaning, bonding (joining) of wafers, and improvement of bonding strength by heat treatment.

[0004] The same process is also applicable to the hybrid bonding technology for simultaneously bonding different materials of an insulating film and a wiring metal, which is a transition metal (copper). In the W2W process, since the wafer surface roughness affects the wafer bonding strength, it is necessary to control the dissolution amount of the wiring metal exposed on the wafer surface in order to avoid wafer bonding failure.

[0005] The insulating film exposed on the wafer surface is harder than the transition metal (copper) which is the wiring metal, and a difference in polishing rate occurs, and a phenomenon called dishing in which the center of the wiring metal is recessed is likely to occur. Therefore, it is very difficult to completely flatten the wafer surface in the wafer surface planarization process before bonding. Therefore, a technology for strictly controlling the dissolution amount of the wiring metal with respect to the insulating film and preventing bonding failure of the insulating film and / or the wiring metal is required.

[0006] As one of them, a technique is being studied in which a predetermined amount of wiring metal is dissolved after wafer surface planarization, and then activation, bonding, and heat treatment of the wafer surface are performed to thermally expand the wiring metal and prevent wafer bonding failure due to unbonding of the insulating film and the wiring metal.

[0007] As an ultra - fine etching method for dissolving a predetermined amount of wiring metal, for example, copper wiring, there is known a method called digital etch in which the surface of the copper wiring is alternately treated with two liquids, diluted hydrogen peroxide water and diluted hydrofluoric acid, to repeat oxidation and dissolution of the copper wiring surface and gradually remove the copper wiring.

[0008] However, in ultra - fine etching techniques such as conventional digital etching, problems such as pattern loading where the amount of metal dissolution varies due to differences in wiring width and non - uniform metal dissolution within the wafer surface occur. Even if ultra - fine etching is achieved, wafer bonding failure may occur, which may have an adverse effect on the performance of the semiconductor.

[0009] In addition, deterioration of the surface roughness of the wiring metal surface after ultra - fine etching leads to wafer bonding failure, so it is necessary not to deteriorate the surface roughness before and after ultra - fine etching.

[0010] However, with conventional etching solutions, the dissolution of copper cannot be precisely controlled, and wafer bonding failure due to unbonding of the insulating film and the wiring metal may occur.

Prior Art Documents

Patent Documents

[0011]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0012] The present invention has been made in view of the above circumstances, and in a semiconductor wiring manufacturing process using copper as a wiring metal, a pH·redox potential adjusting water manufacturing apparatus for manufacturing pH·redox potential adjusting water capable of dissolving a predetermined amount of wiring metal, a method for manufacturing pH·redox potential adjusting water, and a method for manufacturing a semiconductor device are provided.

Means for Solving the Problems

[0013] In order to solve the above problems, the present invention adopts the following configuration. [1] A hydrogen peroxide removal mechanism for removing hydrogen peroxide dissolved in pure water from the pure water, A first branch line and a second branch line branched downstream of the hydrogen peroxide removal mechanism, A confluence line formed by confluence of the first branch line and the second branch line are provided, In the first branch line, a first pH adjusting device for adjusting the pH of the pure water, a redox potential adjusting device for adjusting the redox potential of the pure water, and a first storage tank are arranged in this order. In the second branch line, a second pH adjusting device for adjusting the pH of the pure water and a second storage tank are arranged in this order. The confluence line is configured to alternately circulate a first adjusting water whose pH is adjusted to a range of 9 to 14 and redox potential is adjusted to a range of 0.1 to 1.0 V (vsAg / AgCl) by the first branch line, and a second adjusting water whose pH is adjusted to a range of 0 to 5 by the second branch line, a pH·redox potential adjusting water manufacturing apparatus. [2] The first pH adjusting device adds at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, and tetramethylammonium to the pure water, the pH·redox potential adjusting water manufacturing apparatus according to [1]. [3] The second pH adjusting device adds at least one selected from the group consisting of hydrochloric acid, hydrofluoric acid, citric acid, acetic acid, formic acid, and carbon dioxide to the pure water, the pH·redox potential adjusting water manufacturing apparatus according to [1]. [4] The redox potential adjusting device is the manufacturing device for pH·redox potential adjusted water according to [1], which adds at least one selected from the group consisting of hydrogen peroxide, ozone, and oxygen to the pure water. [5] The manufacturing device for pH·redox potential adjusted water according to [1], wherein a first degassing membrane device and a first gas dissolution membrane device for dissolving an inert gas are provided between the redox potential adjusting device and the first storage tank. [6] The manufacturing device for pH·redox potential adjusted water according to [1], wherein a second degassing membrane device and a second gas dissolution membrane device for dissolving an inert gas are provided between the second pH adjusting device and the second storage tank. [7] The manufacturing device for pH·redox potential adjusted water according to claim 1, wherein the hydrogen peroxide content in the first adjusted water and the second adjusted water is 1000 ppm or less respectively. [8] The manufacturing device for pH·redox potential adjusted water according to [1], wherein the confluence line is connected to a substrate processing device that processes the surface of a semiconductor substrate before bonding the semiconductor substrate having a wiring layer and an insulating layer formed of copper or a copper alloy on the surface to another semiconductor substrate. [9] A hydrogen peroxide removal step of removing hydrogen peroxide dissolved in pure water; A first adjusted water production step of producing a first adjusted water having a pH adjusted to 9 to 14 and a redox potential adjusted to a range of 0.1 to +1.0 V (vsAg / AgCl) by performing a first pH adjustment and a redox potential adjustment on the pure water after the hydrogen peroxide removal step; + A second adjusted water production step of producing a second adjusted water having a pH adjusted to a range of 0 to 5 by performing a second pH adjustment on the pure water after the hydrogen peroxide removal step; A supply step of alternately supplying the first adjusted water and the second adjusted water to a semiconductor manufacturing process by one supply line. A manufacturing method for pH·redox potential adjusted water. ​

[10] The method for producing pH-adjusted and redox-potential-adjusted water according to [9], wherein the first pH adjustment is performed by adding at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, and tetramethylammonium hydroxide to the pure water.

[11] The method for producing pH-adjusted and redox-potential-adjusted water according to [9], wherein the second pH adjustment is performed by adding at least one selected from the group consisting of hydrochloric acid, hydrofluoric acid, citric acid, acetic acid, formic acid, and carbon dioxide to the pure water.

[12] The method for producing pH-adjusted and redox-potential-adjusted water according to [9], wherein the adjustment of the redox potential is performed by adding at least one selected from the group consisting of hydrogen peroxide, ozone, and oxygen to the pure water.

[13] The method for producing pH-adjusted and redox-potential-adjusted water according to [9], wherein a first degassing treatment and a first gas dissolution treatment for dissolving an inert gas are sequentially performed on the pure water after the adjustment of the redox potential.

[14] The method for producing pH-adjusted and redox-potential-adjusted water according to [9], wherein a second degassing treatment and a second gas dissolution treatment for dissolving an inert gas are sequentially performed on the pure water after the second pH adjustment.

[15] The semiconductor manufacturing process is a process of treating the surface of a semiconductor substrate before bonding the semiconductor substrate having a wiring layer and an insulating layer made of copper or a copper alloy on its surface to another semiconductor substrate, and is the method for producing pH-adjusted and redox-potential-adjusted water according to [9].

[16] A step of supplying the first adjusted water produced by the method for producing pH-adjusted and redox-potential-adjusted water according to [9] to

[14] to the surface of a semiconductor substrate having a wiring layer and an insulating layer made of copper or a copper alloy, and forming a copper oxide film on the surface of the wiring layer; A method for manufacturing a semiconductor device, which alternately performs a step of supplying the second adjusted water to the surface of the semiconductor substrate to remove the copper oxide film formed on the surface of the wiring layer.

Advantages of the Invention

[0014] According to the manufacturing apparatus for pH·redox potential adjusted water of the present invention, hydrogen peroxide contained in trace amounts in pure water is removed by a hydrogen peroxide removing mechanism, and the pure water from which the hydrogen peroxide has been removed is supplied to a first branch line and a second branch line, respectively, and pH adjustment and redox potential adjustment are performed so that the desired pH and redox potential are obtained for each branch line. Therefore, two types of pH·redox potential adjusted water can be prepared. And since it is configured such that these two types of pH·redox potential adjusted water alternately flow through a confluence line, it becomes possible to perform digital etching on copper using these two types of pH·redox potential adjusted water as an etching solution. As a result, it becomes possible to dissolve a predetermined amount of wiring metal in the wiring manufacturing process of a semiconductor using copper as a wiring metal. Therefore, according to the present invention, it is possible to provide a manufacturing apparatus for pH·redox potential adjusted water for manufacturing pH·redox potential adjusted water capable of dissolving a predetermined amount of wiring metal in the manufacturing process of a semiconductor using copper as a wiring metal.

[0015] Moreover, according to the manufacturing apparatus for pH·redox potential adjusted water of the present invention, since the first pH adjustment device adds at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, and tetraammonium hydroxide to pure water, the pH of the first adjusted water can be adjusted to a range of 9 to 14.

[0016] Furthermore, according to the manufacturing apparatus for pH·redox potential adjusted water of the present invention, since the second pH adjustment device adds at least one selected from the group consisting of hydrochloric acid, hydrofluoric acid, citric acid, acetic acid, formic acid, and carbon dioxide to the pure water, the pH of the second adjusted water can be adjusted to a range of 0 to 5.

[0017] In addition, according to the manufacturing apparatus for pH·redox potential adjusted water of the present invention, since the redox potential adjustment device adds at least one selected from the group consisting of hydrogen peroxide, ozone, and oxygen to pure water, the redox potential of the first adjusted water can be adjusted to a range of +0.1 to +1.0 V (vsAg / AgCl).

[0018] Further, according to the manufacturing apparatus of pH·redox potential adjusted water of the present invention, between the redox potential adjusting apparatus and the first storage tank, a first degassing membrane apparatus and a first gas dissolution membrane apparatus are provided. By reducing the dissolved oxygen in the first adjusted water by the first degassing membrane apparatus and dissolving an inert gas by the first gas dissolution membrane apparatus, an increase in the dissolved oxygen in the first adjusted water can be prevented, and first adjusted water with a very low level of dissolved oxygen amount can be obtained.

[0019] Further, according to the manufacturing apparatus of pH·redox potential adjusted water of the present invention, between the second pH adjusting apparatus and the second storage tank, a second degassing membrane apparatus and a second gas dissolution membrane apparatus are provided. By reducing the dissolved oxygen in the second adjusted water by the second degassing membrane apparatus and dissolving an inert gas by the second gas dissolution membrane apparatus, an increase in the dissolved oxygen can be prevented, and second adjusted water with a very low level of dissolved oxygen amount can be obtained.

[0020] Further, according to the manufacturing apparatus of pH·redox potential adjusted water of the present invention, since the hydrogen peroxide content in the first adjusted water is 1000 ppm or less, the redox potential of the first adjusted water can be adjusted to a desired range. Also, since the hydrogen peroxide content in the second adjusted water is 1000 ppm or less, it is possible to prevent the second adjusted water from being given excessive oxidizing power.

[0021] Further, according to the manufacturing apparatus of pH·redox potential adjusted water of the present invention, since the confluence line is connected to a substrate processing apparatus that processes the surface of a semiconductor substrate before bonding one semiconductor substrate having a wiring layer and an insulating layer formed of copper or a copper alloy on its surface to another semiconductor substrate, the surface of the semiconductor substrate can be appropriately processed, and for example, the occurrence of wafer bonding failure in the W2W process can be reduced.

Brief Description of the Drawings

[0022]

Figure 1

Figure 2

Embodiments for Carrying Out the Invention

[0023] Hereinafter, an apparatus and a method for producing pH·redox potential-adjusted water, which are embodiments of the present invention, will be described in detail with reference to the drawings.

[0024] 〔First Embodiment〕 <Apparatus for Producing pH·Redox Potential-Adjusted Water> FIG. 1 shows a pH·redox potential-adjusted water production apparatus according to the first embodiment of the present invention. In FIG. 1, the pH·redox potential-adjusted water production apparatus 1 is provided with a platinum group metal-supported resin column 3 as a hydrogen peroxide removal mechanism in a supply line 2 for pure water W, and the supply line 2 for pure water branches into a first branch line 4 and a second branch line 5 after this platinum group metal-supported resin column 3.

[0025] The first branch line 4 is joined by a pH adjuster injection line 41A (first pH adjustment device) provided with a liquid supply mechanism 41B communicating with a pH adjuster tank 41 and a redox potential adjuster injection line 42A (redox potential adjustment device) provided with a liquid supply mechanism 42B communicating with a redox potential adjuster tank 42. A first storage tank 43 for storing the first adjusted water is provided at the subsequent stage of this redox potential adjuster injection line 42A, and this first storage tank 43 is purged with an inert gas IG in this embodiment. Then, the first branch line 4 leads from this first storage tank 43 to a confluence line 6. Note that reference numeral 44 is an on-off valve provided in the first branch line 4 in front of the confluence line 6.

[0026] Further, a pH adjuster injection line 51A (second pH adjustment device) having a liquid supply mechanism 51B communicating with a pH adjuster tank 51 is joined to the second branch line 5. A second storage tank 53 for storing second conditioning water is provided downstream of the pH adjuster injection line 51A, and this second storage tank 53 is purged with an inert gas IG in the present embodiment. Then, the second branch line 5 extends from this second storage tank 53 to a confluence line 6. Note that reference numeral 54 denotes an on-off valve provided in the second branch line 5 in front of the confluence line 6.

[0027] The confluence line 6 (supply line) is a line where the first branch line 4 and the second branch line 5 join, and reaches a use point UP. Reference numeral 7 denotes an on-off valve provided in the middle of the confluence line 6 leading to the use point UP.

[0028] Further, examples of the use point UP reached by the confluence line 6 (supply line) include a substrate processing apparatus for processing a semiconductor substrate. Examples of the substrate processing apparatus include a substrate processing apparatus that processes the surface of a semiconductor substrate having a wiring layer and an insulating layer formed of copper or a copper alloy on its surface before bonding the semiconductor substrate to another semiconductor substrate in order to etch the wiring layer.

[0029] In the present embodiment, downstream of the pH adjuster injection line 41A and the oxidation-reduction potential adjuster injection line 42A of the first branch line 4, for example, in the first storage tank 43, a pH meter as pH measurement means (not shown) and an adjustment water quality monitoring mechanism such as an ORP meter as oxidation-reduction potential measurement means are respectively provided. Further, downstream of the pH adjuster injection line 51A of the second branch line 5, for example, in the second storage tank 53, an adjustment water quality monitoring mechanism such as a pH meter as pH measurement means (not shown) is provided. These pH meters and ORP meters are connected to a control device such as a personal computer. Then, based on the measured values of these pH meters and ORP meters, this control device can control the injection amount of the pH adjuster and the injection amount of the oxidation-reduction potential adjuster.

[0030] <Pure water> In this embodiment, the pure water W used as raw water is preferably ultrapure water having a resistivity of 18.1 MΩ·cm or more, fine particles of 1000 particles / L or less with a particle size of 50 nm or more, viable bacteria of 1 cell / L or less, TOC (Total Organic Carbon) of 1 μg / L or less, total silicon of 0.1 μg / L or less, metals of 1 ng / L or less, ions of 10 ng / L or less, hydrogen peroxide of 30 μg / L or less, and a water temperature of 25 ± 2°C.

[0031] <Hydrogen peroxide removal mechanism> In this embodiment, a platinum group metal-supported resin column 3 is used as the hydrogen peroxide removal mechanism.

[0032] (Platinum group metal) In this embodiment, examples of the platinum group metal supported on the platinum group metal-supported resin used in the platinum group metal-supported resin column 3 include ruthenium, rhodium, palladium, osmium, iridium, and platinum. These platinum group metals can be used alone, in combination of two or more, as an alloy of two or more, or as a purified product of a naturally occurring mixture without separation into individual components. Among these, platinum, palladium, platinum / palladium alloy alone or a mixture of two or more of these can be preferably used because of their strong catalytic activity. Also, nano-order fine particles of these metals can be particularly preferably used.

[0033] (Support resin) In the platinum group metal-supported resin column 3, an ion exchange resin can be used as the support resin for supporting the platinum group metal. Among these, an anion exchange resin can be particularly preferably used. Since platinum-based metals are negatively charged, they are stably supported on the anion exchange resin and are difficult to peel off. The exchange group of the anion exchange resin is preferably in the OH form. The OH form anion exchange resin makes the resin surface alkaline and promotes the decomposition of hydrogen peroxide.

[0034] <pH adjuster injection lines 41A, 51A> In this embodiment, the pH adjuster injection lines 41A and 51A are not particularly limited, and a general drug injection device can be used. The pH adjuster tanks 41 and 51 may have an inert gas supply mechanism. When the pH adjuster is a liquid, a pump such as a diaphragm pump can be used, and it is desirable to provide a mechanism in the pH adjuster tanks 41 and 51 for purging with an inert gas or removing dissolved oxygen in the pH adjuster liquid in the tank using a degassing membrane. Also, a pressure-type pump that places the pH adjuster or the oxidation-reduction potential adjuster in a sealed container together with an inert gas such as N 2 gas and extrudes these agents by the pressure of the inert gas can also be preferably used. When the pH adjuster is a gas, a direct gas-liquid contact device such as a gas permeable membrane module or an ejector can be used.

[0035] <The pH adjuster in the pH adjuster injection line 41A> In this embodiment, the pH adjuster injected from the pH adjuster tank 41 is not particularly limited, and in order to adjust the pH of the first conditioning water to 9 to 14, at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, and tetramethylammonium can be used. When the first conditioning water is used as the cleaning water for a wafer with exposed copper as the wiring material, it is preferably made alkaline. However, an alkali metal solution such as sodium hydroxide may not be suitable because it contains metal components. Therefore, in this embodiment, it is most preferable to use ammonia, tetramethylammonium, or the like. When the pH adjuster is one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, and tetramethylammonium, it is desirable to inject the drug into the ultrapure water supply line by means of a pump or a pressurizing means using an inert gas and a sealed tank.

[0036] <The pH adjuster in the pH adjuster injection line 51A> In this embodiment, the pH adjuster injected from the pH adjuster tank 51 is not particularly limited, and at least one selected from the group consisting of hydrochloric acid, hydrofluoric acid, citric acid, acetic acid, formic acid, and carbon dioxide can be used to adjust the pH of the second adjusted water to 0 to 5. When the pH adjuster is one selected from the group consisting of hydrochloric acid, hydrofluoric acid, citric acid, acetic acid, and formic acid, it is desirable to inject the chemical into the ultrapure water supply line by means of a pump or a pressurizing means using an inert gas in a sealed tank. When the pH adjuster is carbon dioxide, it is desirable to add it by gas dissolution using a gas permeable membrane module or a direct gas-liquid contact device using an ejector.

[0037] <Redox potential adjuster injection line 42A> In this embodiment, the redox potential adjuster injection line 42A is not particularly limited, and a general chemical injection device can be used. The redox potential adjuster tank 42 may have a supply mechanism for an inert gas. When the redox potential adjuster is a liquid, a pump such as a diaphragm pump can be used, and it is desirable to provide a mechanism for purging the inside of the redox potential adjuster tank 42 with an inert gas or removing dissolved oxygen in the pH adjuster liquid in the tank using a degassing membrane. Also, a pressurized pump in which the redox potential adjuster is placed in a sealed container together with an inert gas such as N 2 gas and these agents are extruded by the pressure of the inert gas can also be preferably used. When the redox potential adjuster is a gas, a direct gas-liquid contact device such as a gas permeable membrane module or an ejector can be used.

[0038] <Redox potential adjuster> In this embodiment, there is no particular limitation on the redox potential regulator injected from the redox potential regulator tank 42. However, in order to adjust the redox potential to the range of +0.1 to +1.0 V (vs Ag / AgCl), at least one selected from the group consisting of hydrogen peroxide, ozone, and oxygen can be used. For example, when the first conditioning water is used as the cleaning water for the wafer with exposed copper, since it is preferable to positively adjust the redox potential to suppress the elution of copper, it is preferable to use hydrogen peroxide water.

[0039] <Method for Producing pH and Redox Potential Adjusted Water> A method for producing pH and redox potential adjusted water using the production apparatus 1 of pH and redox potential adjusted water according to this embodiment having the configuration described above will be described below.

[0040] In this embodiment, a hydrogen peroxide removal step, a first conditioning water production step, a second conditioning water production step, and a supply step are performed. The first conditioning water production step and the second conditioning water production step may be performed simultaneously, or the first conditioning water production step and the second conditioning water production step may be performed alternately in any order.

[0041] The hydrogen peroxide removal step is a step of removing hydrogen peroxide dissolved in pure water from the pure water. In the first conditioning water production step, the pure water after the hydrogen peroxide removal step is subjected to a first pH adjustment and a redox potential adjustment, so that the pH is 9 to 14 and the redox potential is + Adjusted to the range of 0.1 to +1.0 V (vs Ag / AgCl) to produce the first conditioning water. In the second conditioning water production step, the pure water after the hydrogen peroxide removal step is subjected to a second pH adjustment to produce the second conditioning water having a pH adjusted to the range of 0 to 5. In the supply step, the first conditioning water and the second conditioning water are alternately supplied to the semiconductor manufacturing process through one supply line.

[0042] Hereinafter, the details of each step will be described while explaining the method for producing the first conditioning water and the method for producing the second conditioning water.

[0043] (Method for Producing First Adjusted Water) Since pure water W as raw water generally contains hydrogen peroxide at a level of several tens of ppb, it is necessary to remove the hydrogen peroxide in pure water W in advance in order to accurately control the oxidation-reduction potential of the cleaning liquid. Therefore, as a hydrogen peroxide removal step, pure water W is supplied from supply line 2 to a platinum group metal-supported resin column 3. In this platinum group metal-supported resin column 3, the hydrogen peroxide in pure water W is decomposed and removed by the catalytic action of the platinum group metal, that is, it functions as a hydrogen peroxide removal mechanism. Then, this pure water W branches into a first branch line 4 and a second branch line 5.

[0044] And in the first branch line 4, as the first pH adjustment, a pH adjuster is injected from the pH adjuster tank 41. The addition of this pH adjuster may be appropriately set according to the desired pH, the flow rate of the first branch line 4, and the concentration of the pH adjuster. For example, when making it alkaline during the cleaning of a semiconductor having fine copper wiring, an amount that makes the pH of the cleaning liquid fall within the range of 9 to 14 may be added.

[0045] Next, as the adjustment of the oxidation-reduction potential, an oxidation-reduction potential adjuster is injected from the oxidation-reduction potential adjuster tank 42. The addition of this oxidation-reduction potential adjuster may be appropriately set according to the desired oxidation-reduction potential, the flow rate of the first branch line 4, and the concentration of the oxidation-reduction potential adjuster. For example, for the cleaning of a semiconductor having fine copper wires, an amount that makes the oxidation-reduction potential of the cleaning liquid fall within the range of +0.1 to +1.0 V (vsAg / AgCl) may be added.

[0046] It is desirable that the first adjusted water W1 adjusted by the first branch line 4 has a pH of 9 or more and 14 or less, and an oxidation-reduction potential of +0.1 V or more and +1.0 V or less (vsAg / AgCl). Also, it is desirable that the concentration of hydrogen peroxide in the first adjusted water W1 is 1000 ppm or less.

[0047] In this way, once the first adjusted water W1 is produced, it is stored in the first storage tank 43. Since this first storage tank 43 is purged with an inert gas, oxygen and carbon dioxide gas can be prevented from dissolving in the obtained first adjusted water W1 during storage, thereby preventing fluctuations in pH and oxidation-reduction potential. At this time, based on the measurement results of a pH meter and an ORP meter (not shown), by controlling the addition amount of the pH adjuster from the pH adjuster tank 41 and the addition amount of the oxidation-reduction potential adjuster from the oxidation-reduction potential adjuster tank 42 with a control device, the first adjusted water W1 adjusted to the desired pH and oxidation-reduction potential can be stably supplied.

[0048] (Method for Producing Second Adjusted Water) On the other hand, the pure water W branched to the second branch line 5 is used to produce the second adjusted water W2 by injecting a pH adjuster from the pH adjuster tank 51 for the second pH adjustment in the same manner as in the case of the first adjusted water W1. At this time, based on the measurement results of a pH meter (not shown), by controlling the addition amount of the pH adjuster from the pH adjuster tank 51 with a control device, the second adjusted water W2 with the desired pH can be stably supplied.

[0049] The second adjusted water W2 preferably has a pH of 0 or more and 5 or less. Also, the concentration of hydrogen peroxide in the second adjusted water W2 is preferably 1000 ppm or less.

[0050] Then, the first adjusted water W1 and the second adjusted water W2 produced in this way are sent as a supply process to the use point UP via the confluence line 6. At this time, in the confluence line 6, it is preferable to alternately send a fixed amount of the first adjusted water W1 and a fixed amount of the second adjusted water W2. To alternately send a fixed amount of the first adjusted water W1 and a fixed amount of the second adjusted water W2, the control valves 44, 54, and 7 may be controlled by a control device (not shown) to achieve the alternate liquid supply.

[0051] (Supply Example of pH·Oxidation-Reduction Potential Adjusted Water) Hereinafter, a case where the first adjustment water W1 and the second adjustment water W2 manufactured as described above are used for the ultra-fine etching process of a wiring made of copper will be described as an example.

[0052] In this embodiment, the first adjustment water and the second adjustment water are alternately supplied to the semiconductor manufacturing process through one supply line (the confluence line 6). Here, as the semiconductor manufacturing process, it is preferably a process of treating the surface of a semiconductor substrate before bonding a semiconductor substrate having a wiring layer and an insulating layer made of copper or a copper alloy on its surface to another semiconductor substrate. More specifically, it may be a process of etching the copper wiring formed on the surface of the semiconductor substrate by a digital etching method.

[0053] A technique called digital etching is used in the ultra-fine etching of a wiring made of copper or a copper alloy. This is a technique that repeatedly oxidizes the metal surface and dissolves the oxide film, gradually dissolving the metal. When performing ultra-fine etching of copper by digital etching, in the first step, a copper oxide film is formed on the surface of the copper wiring without dissolving the copper by the first adjustment water, and in the second step, only the copper oxide film formed in the first step needs to be dissolved without dissolving the copper by the second adjustment water.

[0054] According to the Pourbaix diagram showing what chemical species of a metal are most stable in an aqueous solution under certain [potential - pH] conditions, copper becomes passive and difficult to dissolve under alkaline conditions, especially in the region where the pH is 9 to 12. In particular, by adding hydrogen peroxide in an amount of about 10 to 1000 ppm to an alkaline solution with a pH of 9 to 12, the dissolution rate of copper becomes the minimum. However, it is known that when the pH is 12 or more and the hydrogen peroxide concentration is 100 to 1000 ppm or more, the dissolution rate of copper becomes about 50 times that when hydrogen peroxide is not added. Therefore, in order to oxidize the surface while preventing the dissolution of copper in the first step of digital etching, it is necessary to more precisely control the pH and the oxidation-reduction potential of the first adjustment water.

[0055] On the one hand, according to the Pourbaix diagram, under acidic conditions, behaviors such as dissolution and passivation vary depending on the differences in the pH and redox potential of the aqueous solution. In order to etch a predetermined amount of copper in a minute amount within a predetermined time, it is necessary to accelerate the removal rate of the copper oxide film in the second step. For this purpose, it is necessary to make the pH of the second conditioning water less than 5.

[0056] In view of these, in order to etch a predetermined amount of copper in a minute amount within a predetermined time while suppressing the occurrence of pattern loading, the redox potential is adjusted in the range of pH 9 to 14 so that the pH and redox potential are such that copper dissolution is least likely to occur, and the redox potential is 0.1 to 1.0 V (vs Ag / AgCl) (hydrogen peroxide is about 10 to 1000 ppm). The first conditioning water W1 is adjusted and supplied from the first branch line 4 to the substrate processing apparatus which is the use point UP to perform the cleaning in the first step. Thereby, an oxide film is formed on the surface of the copper without dissolving the copper. At this time, the on-off valve 54 of the second branch line is closed.

[0057] Next, in order to etch a predetermined amount of copper in a minute amount within a predetermined time, in order to accelerate the removal rate of the copper oxide film, hydrofluoric acid, citric acid, acetic acid, formic acid, and carbon dioxide are added so that the pH of the treatment liquid becomes less than 5 to produce the second conditioning water W2. Then, the on-off valve 44 of the first branch line 4 is closed to stop the supply of the first conditioning water W1, the on-off valve 54 of the second branch line 5 is opened, and the second conditioning water W2 is supplied from the second branch line 5 to the substrate processing apparatus which is the use point UP to perform the cleaning in the second step. Thereby, a predetermined amount of copper is etched in a minute amount.

[0058] In this way, minute etching of the wiring of a semiconductor having a wiring made of copper or a copper alloy can be efficiently performed in a short time. Thereby, the surface of the semiconductor substrate can be appropriately processed, and for example, the occurrence of wafer bonding failure in the W2W process can be reduced.

[0059] 〔Second Embodiment〕 <Apparatus for Producing pH·Redox Potential Adjusted Water> FIG. 2 shows a pH·redox potential adjusted water production apparatus 11 according to the second embodiment of the present invention. The same components as those in the above-described first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

[0060] In FIG. 2, the pH·redox potential adjusted water production apparatus 11 includes a first degassing membrane apparatus 47 having a vacuum pump 47A downstream of the redox potential adjusting agent tank 42 in the first branch line 4, and a first gas dissolution membrane apparatus 48 for dissolving an inert gas. Further, the second branch line 5 includes a second degassing membrane apparatus 57 having a vacuum pump 57A downstream of the pH adjusting agent tank 51, and a second gas dissolution membrane apparatus 58 for dissolving an inert gas.

[0061] The first degassing membrane apparatus 47 and the second degassing membrane apparatus 57 are membrane-type degassing apparatuses, and vacuum pumps (VPs) 47A and 57A are connected to the gas phase side of the degassing membrane. In these degassing membrane apparatuses 47 and 57, the first adjusted water W1 or the second adjusted water W2 is respectively passed through one side (liquid phase side) of the degassing membrane, and the other side (gas phase side) is sucked by the vacuum pumps (VPs) 47A and 57A, so that dissolved gases such as dissolved oxygen are removed by permeating through the degassing membrane and migrating to the gas phase chamber side. The degassing membrane may be a membrane that allows gases such as oxygen, nitrogen, and steam to pass through but does not allow water to permeate. For example, there are silicon rubber-based, polytetrafluoroethylene-based, polyolefin-based, polyurethane-based, etc. Various commercially available products can be used as this degassing membrane.

[0062] The first gas dissolution membrane apparatus 48 and the second gas dissolution membrane apparatus 58 are each provided with a gas dissolution membrane. The gas phase chamber side of the gas dissolution membrane is connected to a gas source as an inert gas N 2 . In these gas dissolution membrane apparatuses 48 and 58, the first adjusted water W1 or the second adjusted water W2 is respectively passed through one side (liquid phase side) of the gas dissolution membrane, and N 2 gas is supplied to the other side (gas phase side), so that an inert gas is dissolved in the first adjusted water W1 and the second adjusted water W2, respectively. Note that the inert gas is not limited to N 2 gas, and argon, helium, etc. can also be preferably used.

[0063] <Method for producing pH-adjusted and redox potential-adjusted water> A method for producing pH-adjusted and redox potential-adjusted water using the production apparatus for pH-adjusted and redox potential-adjusted water of the present embodiment having the configuration as described above will be described below.

[0064] (Method for producing first adjusted water) Since pure water W as raw water generally contains hydrogen peroxide at the level of several tens of ppb, in order to accurately control the redox potential of the cleaning liquid, it is necessary to remove hydrogen peroxide in pure water W in advance. Therefore, first, pure water W is supplied from the supply line 2 to the platinum group metal-supported resin column 3. In this platinum group metal-supported resin column 3, hydrogen peroxide in pure water W is decomposed and removed by the catalytic action of the platinum group metal, that is, it functions as a hydrogen peroxide removal mechanism. Then, this pure water W branches into a first branch line 4 and a second branch line 5.

[0065] And in the first branch line 4, a pH adjuster is injected from the pH adjuster tank 41. The addition of this pH adjuster may be appropriately set according to the desired pH, the flow rate of the first branch line 4, and the concentration of the pH adjuster. For example, for cleaning a semiconductor having a fine copper wire, an amount may be added such that the pH of the first adjusted water W1 is in the range of 9 to 14.

[0066] Next, a redox potential adjuster is injected from the redox potential adjuster tank 42. The addition of this redox potential adjuster may be appropriately set according to the desired redox potential, the flow rate of the first branch line 4, and the concentration of the redox potential adjuster. For example, for cleaning a semiconductor having a fine copper wire, an amount may be added such that the redox potential of the first adjusted water W1 is in the range of 0.1 to 1.0 V (vsAg / AgCl).

[0067] Next, the first adjusted water W1 after the redox potential adjustment is degassed by the first degassing membrane device 47. In the first degassing membrane device 47, the first adjusted water W1 is made to flow on the liquid phase chamber side of the liquid phase chamber and the gas phase chamber, which are constituted by a hydrophobic gas permeable membrane, and the gas phase chamber is depressurized by a vacuum pump (VP) 47A, so that dissolved gases such as dissolved oxygen contained in the first adjusted water W1 are transferred to the gas phase chamber through the hydrophobic gas permeable membrane and removed. Thereby, the dissolved oxygen concentration of the first adjusted water W1 can be reduced to a very low level. Further, by not directly degassing the pH adjuster and the redox potential adjuster and degassing them after making them the first adjusted water W1, the risk of chemical liquid leakage and the like when these chemicals are vacuum degassed can be reduced.

[0068] Next, an inert gas is supplied to the first adjusted water W1 after the degassing treatment by the first gas dissolution membrane device 48 to stabilize the properties of the first adjusted water W1, whereby the stabilized first adjusted water W1 can be produced.

[0069] After producing the first adjusted water W1 in this way, it is stored in the first storage tank 43. Since this first storage tank 43 is purged with an inert gas, it is possible to prevent oxygen and carbon dioxide gas from dissolving in the obtained first adjusted water W1 and the pH and redox potential from fluctuating while the first adjusted water W1 is being stored.

[0070] (Method for producing the second adjusted water) On the other hand, the pure water branched to the second branch line 5 is, in the same manner as in the case of the first adjusted water W1, injected with a pH adjuster from the pH adjuster tank 51, further degassed by the second degassing membrane device 57, and then an inert gas is dissolved in the second gas dissolution membrane device 58, whereby the second adjusted water W2 can be produced.

[0071] Then, the first adjusted water W1 and the second adjusted water W2 thus manufactured are fed to a substrate processing apparatus, which is a use point UP, via the confluence line 6. At this time, in the confluence line 6, it is preferable to alternately feed a fixed amount of the first adjusted water W1 and a fixed amount of the second adjusted water W2. To alternately feed a fixed amount of the first adjusted water W1 and a fixed amount of the second adjusted water W2, the on-off valves 44, 54, and 7 may be controlled by a control device (not shown) to achieve the alternate liquid feeding.

[0072] According to the manufacturing apparatus and manufacturing method of the pH·redox potential adjusted water of the present embodiment, since two types of pH·redox potential adjusted water having different pH and redox potentials can be manufactured, by combining these different pH·redox potential adjusted water, it is possible to wash a semiconductor with washing water having a pH and redox potential capable of suppressing copper dissolution and washing water having a pH and redox potential capable of finely adjusting copper dissolution, and it is possible to dissolve a predetermined amount of the wiring metal in the wiring manufacturing process of a semiconductor using copper as the wiring metal. Thereby, for example, the occurrence of wafer bonding defects in the W2W process can be reduced.

Example

[0073] [Example 1] (Preparation of the first adjusted water and the second adjusted water) Using the manufacturing apparatus of the pH·redox potential adjusted water shown in FIG. 1, in the first branch line 4, ammonia was added to pure water W from the pH adjuster tank 41, and hydrogen peroxide water was added from the redox potential adjuster tank 42, respectively, to produce an ammonia·hydrogen peroxide aqueous solution (ammonia concentration: 2 ppm, pH 9 (23 °C), hydrogen peroxide concentration: 1000 ppm, redox potential: +0.28 V) as the first adjusted water W1. Also, in the second branch line, hydrochloric acid was added to pure water W from the pH adjuster tank 51 to produce a hydrochloric acid aqueous solution (hydrochloric acid concentration: 1000 ppm, pH 2 (23 °C), hydrogen peroxide concentration: 0 ppb) as the second adjusted water W2.

[0074] (Digital etch treatment test) A 20 mm × 20 mm square test piece was cut out from a 300 mm Φ copper wiring (100 μL / S pattern) and a wafer with an insulating film. This test piece was immersed in the first conditioning water and the second conditioning water at 23°C for 20 minutes each, and then the test pieces were joined to each other. As a result, no bonding failure was observed by optical microscopy in the copper wiring and the insulating film, so it was good.

[0075] [Example 2] (Preparation of the first conditioning water and the second conditioning water) As the first conditioning water W1, an aqueous ammonia-hydrogen peroxide solution (ammonia concentration: 10 ppm, pH 10 (23°C), hydrogen peroxide concentration: 1000 ppm, oxidation-reduction potential: +0.20 V) was produced. Also, in the second branch line, hydrofluoric acid was added from the pH adjuster tank 51 to pure water W, and an aqueous hydrofluoric acid solution (hydrofluoric acid concentration: 1000 ppm, pH 2 (23°C), hydrogen peroxide concentration: 0 ppb) was produced as the second conditioning water W2.

[0076] (Digital etch treatment test) A 20 mm × 20 mm square test piece was cut out from a 300 mm Φ copper wiring (100 μL / S pattern) and a wafer with an insulating film. This test piece was immersed in the first conditioning water and the second conditioning water at 23°C for 20 minutes each, and then the test pieces were joined to each other. As a result, no bonding failure was observed by optical microscopy in the copper wiring and the insulating film, so it was good.

[0077] [Example 3] (Preparation of the first conditioning water and the second conditioning water) As the first conditioning water W1, an aqueous ammonia-hydrogen peroxide solution (ammonia concentration: 100 ppm, pH 11 (23°C), hydrogen peroxide concentration: 1000 ppm, oxidation-reduction potential: +0.18 V) was produced. Also, in the second branch line, sulfuric acid was added from the pH adjuster tank 51 to pure water W, and an aqueous sulfuric acid solution (sulfuric acid concentration: 1000 ppm, pH 2 (23°C), hydrogen peroxide concentration: 0 ppb) was produced as the second conditioning water W2.

[0078] (Digital Etching Treatment Test) A 20 mm × 20 mm square test piece was cut out from a 300 mm Φ copper wiring (100 μL / S pattern) and a wafer with an insulating film. This test piece was immersed in the first conditioning water and the second conditioning water at 23°C for 20 minutes each, and then the test pieces were joined to each other. As a result, since no bonding failure was observed in the copper wiring and the insulating film under an optical microscope, it was good.

[0079] [Example 4] (Preparation of the First Conditioning Water and the Second Conditioning Water) In the first branch line 4, sodium hydroxide was added from the pH adjuster tank 41 to pure water W, and hydrogen peroxide water was added from the oxidation-reduction potential adjuster tank 42 to produce a sodium hydroxide-hydrogen peroxide aqueous solution (sodium hydroxide concentration: 10 ppm, pH 10 (23°C), hydrogen peroxide concentration: 1000 ppm, oxidation-reduction potential: +0.21 V) as the first conditioning water W1. Also, in the second branch line, acetic acid was added from the pH adjuster tank 51 to pure water W to produce an acetic acid aqueous solution (acetic acid concentration: 1000 ppm, pH 3 (23°C), hydrogen peroxide concentration: 0 ppb) as the second conditioning water W2.

[0080] (Digital Etching Treatment Test) A 20 mm × 20 mm square test piece was cut out from a 300 mm Φ copper wiring (100 μL / S pattern) and a wafer with an insulating film. This test piece was immersed in the first conditioning water and the second conditioning water at 23°C for 20 minutes each, and then the test pieces were joined to each other. As a result, since no bonding failure was observed in the copper wiring and the insulating film under an optical microscope, it was good.

[0081] [Example 5] (Preparation of the First Conditioning Water and the Second Conditioning Water) An ammonia-hydrogen peroxide aqueous solution (ammonia concentration: 10 ppm, pH 10 (23°C), hydrogen peroxide concentration: 1000 ppm, oxidation-reduction potential: +0.20 V) was produced as the first conditioning water W1. Also, in the second branch line, hydrochloric acid was added from the pH adjuster tank 51 to pure water W to produce an aqueous hydrochloric acid solution (hydrochloric acid concentration: 10%, pH 1 (23°C), hydrogen peroxide concentration: 100 ppb) as the second adjusted water W2.

[0082] (Digital etch treatment test) A 20 mm × 20 mm square test piece was cut out from a 300 mm Φ copper wiring (100 μL / S pattern) and a wafer with an insulating film. This test piece was immersed in the first adjusted water and the second adjusted water at 23°C for 20 minutes each, and then the test pieces were joined to each other. As a result, since no bonding failure was observed by an optical microscope in the copper wiring and the insulating film, it was good.

[0083] [Example 6] (Preparation of the first adjusted water and the second adjusted water) An aqueous ammonia solution (ammonia concentration: 10 ppm, pH 10 (23°C), hydrogen peroxide concentration: 0 ppm, oxidation-reduction potential: +0.37 V) was produced as the first adjusted water W1. Also, in the second branch line, hydrochloric acid was added from the pH adjuster tank 51 to pure water W to produce an aqueous hydrochloric acid solution (hydrochloric acid concentration: 1 ppm, pH 5 (23°C), hydrogen peroxide concentration: 0 ppb) as the second adjusted water W2.

[0084] (Digital etch treatment test) A 20 mm × 20 mm square test piece was cut out from a 300 mm Φ copper wiring (100 μL / S pattern) and a wafer with an insulating film. This test piece was immersed in the first adjusted water and the second adjusted water at 23°C for 20 minutes each, and then the test pieces were joined to each other. As a result, since bonding failure was partially observed by an optical microscope in the copper wiring and the insulating film, it was fair.

[0085] [Comparative Example 1] A 20 mm × 20 mm square test piece was cut out from a wafer with a 300 mm Φ copper wiring (100 μL / S pattern) and an insulating film. Without performing any treatment on this test piece, the test pieces were joined to each other. As a result, since a bonding defect was observed in the copper wiring and the insulating film under an optical microscope, it was defective.

[0086] [Comparative Example 2] (Preparation of First Adjusting Water and Second Adjusting Water) As the first adjusting water W1, an aqueous hydrogen peroxide solution (pH 5 (23 °C), hydrogen peroxide concentration: 3%, oxidation-reduction potential: +0.57 V) was produced. Also, as the second adjusting water W2, an aqueous hydrofluoric acid solution (hydrofluoric acid concentration: 0.05%, pH 3 (23 °C), hydrogen peroxide concentration: 10 ppb) was produced.

[0087] Then, a 20 mm × 20 mm square test piece was cut out from a wafer with a 300 mm Φ copper wiring (100 μL / S pattern) and an insulating film. This test piece was immersed in the first adjusting water and the second adjusting water for 20 minutes each at 23 °C, and then the test pieces were joined to each other. As a result, since a bonding defect was observed in the copper wiring and the insulating film under an optical microscope, it was defective.

[0088] [Comparative Example 3] An aqueous sodium hydroxide solution (sodium hydroxide concentration: 1000 ppm, pH 13 (23 °C), oxidation-reduction potential: +0.05 V) in which sodium hydroxide was dissolved in pure water was produced.

[0089] Then, a 20 mm × 20 mm square test piece was cut out from a wafer with a 300 mm Φ copper wiring (100 μL / S pattern) and an insulating film. This test piece was immersed in the aqueous sodium hydroxide solution for 20 minutes at 23 °C, and then the test pieces were joined to each other. As a result, since a bonding defect was observed in the copper wiring and the insulating film under an optical microscope, it was defective.

[0090] The results of the examples and comparative examples are shown in Table 1.

[0091]

Table 1

Explanation of Symbols

[0092] 1,... pH and Redox Potential Adjusted Water Production Apparatus, 2... Supply Line, 3... Platinum Group Metal Supported Resin Column (Hydrogen Peroxide Removal Mechanism), 4... First Branch Line, 5... Second Branch Line, 6... Confluence Line, 41A... pH Adjusting Agent Injection Line (First pH Adjusting Device), 42A... Redox Potential Adjusting Agent Injection Line (Redox Potential Adjusting Device), 43... First Storage Tank, 47... First Degassing Membrane Device, 48... First Gas Dissolution Membrane Device, 51A... pH Adjusting Agent Injection Line (Second pH Adjusting Device), 53... Second Storage Tank, 57... Second Degassing Membrane Device, 58... Second Gas Dissolution Membrane Device.

Claims

1. a hydrogen peroxide removal mechanism for removing hydrogen peroxide dissolved in the pure water from the pure water; a first branch line and a second branch line branched off at a downstream side of the hydrogen peroxide removal mechanism; a junction line formed by junction of the first branch line and the second branch line, a first pH adjusting device for adjusting a pH of the pure water, an oxidation-reduction potential adjusting device for adjusting an oxidation-reduction potential of the pure water, and a first storage tank are arranged in this order in the first branch line; a second pH adjusting device for adjusting a pH of the pure water and a second storage tank are arranged in this order in the second branch line; The confluence line is configured to alternately circulate first adjusted water, the pH of which has been adjusted to a range of 9 to 14 and the redox potential of which has been adjusted to a range of 0.1 to 1.0 V (vs Ag / AgCl) by the first branch line, and second adjusted water, the pH of which has been adjusted to a range of 0 to 5 by the second branch line.

2. 2. The apparatus for producing pH / oxidation-reduction potential adjusted water as described in claim 1, wherein the first pH adjustment device adds at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, and tetrahydroammonium to the pure water.

3. The apparatus for producing pH / oxidation-reduction potential adjusted water as described in claim 1, wherein the second pH adjustment device adds at least one selected from the group consisting of hydrochloric acid, hydrofluoric acid, citric acid, acetic acid, formic acid and carbon dioxide to the pure water.

4. 2. The apparatus for producing pH / oxidation-reduction potential adjusted water according to claim 1, wherein the oxidation-reduction potential adjusting device adds at least one selected from the group consisting of hydrogen peroxide, ozone, and oxygen to the pure water.

5. The apparatus for producing pH / oxidation-reduction potential adjusted water as described in claim 1, further comprising a first degassing membrane device and a first gas dissolution membrane device for dissolving an inert gas between the oxidation-reduction potential adjustment device and the first storage tank.

6. The apparatus for producing pH / oxidation-reduction potential adjusted water as described in claim 1, further comprising a second degassing membrane device and a second gas dissolution membrane device for dissolving an inert gas between the second pH adjustment device and the second storage tank.

7. 2. The apparatus for producing pH / oxidation-reduction potential adjusted water according to claim 1, wherein the first adjusted water and the second adjusted water each have a hydrogen peroxide content of 1000 ppm or less.

8. The pH / oxidation-reduction potential adjusted water manufacturing apparatus of claim 1, wherein the junction line is connected to a substrate processing apparatus that processes the surface of a semiconductor substrate having a wiring layer and an insulating layer made of copper or a copper alloy formed on its surface before the semiconductor substrate is bonded to another semiconductor substrate.

9. a hydrogen peroxide removal step of removing hydrogen peroxide dissolved in the pure water from the pure water; a first adjusted water producing step of producing a first adjusted water having a pH adjusted to 9 to 14 and an oxidation-reduction potential adjusted to +0.1 to +1.0 V (vs Ag / AgCl) by performing a first pH adjustment and an oxidation-reduction potential adjustment on the pure water after the hydrogen peroxide removal step; a second adjusted water producing step of producing a second adjusted water having a pH adjusted to a range of 0 to 5 by performing a second pH adjustment on the pure water after the hydrogen peroxide removing step; a supplying step of alternately supplying the first adjusted water and the second adjusted water to a semiconductor manufacturing process through one supply line.

10. 10. The method for producing pH / oxidation-reduction potential adjusted water according to claim 9, wherein the first pH adjustment is performed by adding at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, and tetrahydroammonium to the pure water.

11. 10. The method for producing pH / oxidation-reduction potential adjusted water according to claim 9, wherein the second pH adjustment is performed by adding at least one selected from the group consisting of hydrochloric acid, hydrofluoric acid, citric acid, acetic acid, formic acid and carbon dioxide to the pure water.

12. 10. The method for producing pH / oxidation-reduction potential adjusted water according to claim 9, wherein the oxidation-reduction potential is adjusted by adding at least one selected from the group consisting of hydrogen peroxide, ozone, and oxygen to the pure water.

13. 10. The method for producing pH / oxidation-reduction potential adjusted water according to claim 9, further comprising sequentially carrying out a first degassing treatment and a first gas dissolution treatment for dissolving an inert gas in the pure water after the adjustment of the oxidation-reduction potential.

14. 10. The method for producing pH / oxidation-reduction potential adjusted water according to claim 9, further comprising sequentially carrying out a second degassing treatment and a second gas dissolution treatment for dissolving an inert gas on the pure water after the second pH adjustment.

15. The method for producing pH / oxidation-reduction potential adjusted water as described in claim 9, wherein the semiconductor manufacturing process is a process for treating the surface of a semiconductor substrate having a wiring layer and an insulating layer made of copper or a copper alloy formed on the surface thereof before bonding the semiconductor substrate to another semiconductor substrate.

16. a step of supplying the first adjusted water produced by the method for producing pH / oxidation-reduction potential adjusted water according to any one of claims 9 to 14 to a surface of a semiconductor substrate on which a wiring layer made of copper or a copper alloy and an insulating layer are formed, to form a copper oxide film on the surface of the wiring layer; and a step of supplying the second regulated water to the surface of the semiconductor substrate to remove a copper oxide film formed on the surface of the wiring layer.

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